The overarching aims of this application are three-fold: 1) To perform rigorous patient-based research studies in a new direction aimed at the identification of the predictors of cognitive aging and structural brain integrity across the lifecourse among biracial adults, 2) To use the applicant's research as a platform for the mentorship of patient-oriented researchers in the epidemiology of cognitive aging and 3) To enable the applicant to pursue new research directions and to continue to support her development as an internationally recognized mentor for trainees from a wide range of disciplines interested in cognitive aging. Dr. Yaffe's long-term goals are to become an international leader in aging research, to contribute substantially to our understanding and approaches to the treatment and prevention of cognitive impairment and to mentor the "next generation" of investigators interested in the epidemiology of cognitive aging. The identification of who is at risk for cognitive impairment associated with aging remains one of the most important goals of our time. By increasing our understanding of cognitive function in midlife and identifying earlier risk factors extending from early adulthood, it may be possible to intervene to prevent dementia and maintain healthy brain aging. In addition, knowledge of the lifecourse antecedents, including the timing and cumulative risk of exposure, of cognitive aging could inform the nature of these interventions.